The Mousetrap Themes

Themes and Meanings

All mysteries are morality plays, in which evil does not usually go unpunished. Mrs. Stanning killed a child, and though she served time in prison, “prison wasn’t bad enough for her,” as Trotter says. Although he is insane, he echoes his creator’s sentiments. Agatha Christie believed that capital punishment was just, that only a life can pay for a life, unless the murderer is not morally responsible, as Trotter clearly is not. Therefore he will be placed in an insane asylum. She also recognized that misfortune can befall those who are technically innocent of wrongdoing, for, as in a Shakespearean tragedy, once evil is unleashed, it cannot be controlled—thus the need for justice.

One sees in this play, too, one of the worst effects of crime: its creation of suspicion. The Ralstons love each other enough to brave a blizzard to go to London for anniversary presents, and they are working together to make their guest house succeed. Yet by the second act each suspects the other of infidelity, even of murder, and none of the guests trusts either fellow guests or the hosts.

Though the primary cause of this unease is the murder, social change also plays a role. Trotter points out that in the postwar world “there aren’t any backgrounds nowadays and young people settle their own affairs.” Mollie knew Giles only three weeks before she married him. Although the traditional mystery posits a well-ordered world in which crime is a temporary...